Original Vintage Sketched Paintings of London - People on Train

We can’t find anything out about this artist (Al Ittman? A Littman?) but his or her rapid sketches are lovely. We imagine this artist scooting around London on the tube, presumably on their way to work and catching scenes when spare time allowed, on their lunch break perhaps or in the early evening. Ink and paint on paper. We’re guessing 1960s.